An internal combustion engine typically combusts a mixture of a fuel and an oxidant such as air, to produce mechanical power. Introduction of the fuel into a cylinder of the internal combustion engine is most commonly achieved using a fuel injector. A commonly used injector is a closed-nozzle injector which includes a nozzle assembly having a spring-biased needle valve element positioned adjacent an injector nozzle for allowing the fuel to be injected into the cylinder of the internal combustion engine. The needle valve element moves to allow the fuel to pass through the injector nozzle and out of injector orifices or spray holes, thus, marking the beginning of a fuel injection event.
The fuel supplied by the injector comes in contact with pressurized oxidant, and gets ignited. For an efficient combustion process to occur, efficient mixing of the fuel with the oxidant is necessary. The oxidant may be typically introduced in the combustion chamber through an inlet port, which may be coupled to a source of oxidant. However, in such an arrangement, the fuel comes into contact with the oxidant after the fuel is injected into the combustion chamber resulting in inadequate mixing of the fuel and the oxidant. As the fuel starts burning in a very short span of time after being injected, there is a need for an improved mixing of the fuel and the oxidant.
German Patent Application Number DL 10200/4021538 describes a fluid flow control valve. The fluid flow control valve includes two coaxial valve needles. An inner needle is completely enclosed inside an outer needle. Flow of fuel to jets in the outer needle is blocked by the inner needle. Large diameter jets in the hollow conical nozzle body are provided in line with the jets in the outer needle. The outer needle blocks additional flow to jets in a conical nozzle. The inner and the outer needles together provide a set of injection openings to inject fuel into the combustion chamber.